Diode Detectors

Diode detectors or, as they are more formally known, Zero Bias Schottky Diode Detectors are often used in RF/microwave applications where no primary DC power is available. They are used as a key component in frequency mixers and RF power detector circuits.

The concept for the diode detector is credited to Walter H. Schottky, a German physicist and the inventor of the screen-grid vacuum tube . He was also the son of German mathematician, Friedrich Hermann Schottky.

He discovered that a junction with a specific combination of metals and a doped semiconductor material could rectify, called the Schottky Contact. The Schottky diode junction is formed by plating a extremely pure metal onto a wafer that has already been doped by either a p-type or n-type dopant atoms.

The performance of the diode detector is dependent upon the saturation current. This can lead to a performance degregation at both the high and low temperature extremes because the the saturation current is a strong function of temperature.

The Schottky diode is an order of magnitude faster than standard PN diodes, making it ideal for RF and microwave applications. It has a low junction capacitance, as well as excellent sensitivity and bandwidth. These facts make it ideal for navigation systems, radar, wireless networks, and radio controlled transmitters.